Japan SPOTLIGHT 2016 July/August pp. 28-pp. 33 “Future Advanced Driving Support System with Automated Driving Technology” discloses a background subtraction method for detecting a dynamic object. According to this method, the measurement result of a sensor at a time when no dynamic object is present is stored in a database as static object information. Then, the static object information is compared to the measurement result of the sensor at each time. The difference between both (part where both do not correspond) is detected as the dynamic object.